TW201727751A - Features for improving process uniformity in a millisecond anneal system - Google Patents

Abstract

Systems and methods for improving process uniformity in a millisecond anneal system are provided. In some implementations, a process for thermally treating a substrate in a millisecond anneal system can include obtaining data indicative of a temperature profile associated with one or more substrates during processing in a millisecond anneal system. The process can include one or more of (1) changing the pressure inside the processing chamber of the millisecond anneal system; (2) manipulating the irradiation distribution by way of the refracting effect of a water window in the millisecond anneal system; (3) adjusting the angular positioning of the substrate; and/or (4) configuring the shape of the reflectors used in the millisecond anneal system.

Description

Method for improving uniformity of processing in millisecond annealing system

The present application claims the benefit of priority to U.S. Provisional Patent Application Serial No. 62/272, the entire disclosure of which is incorporated herein by reference.

The present invention relates generally to thermal processing chambers, and more particularly to processing millisecond annealing thermal processing chambers such as semiconductor substrates.

The millisecond annealing system can be used for semiconductor processing for ultra-rapid thermal processing of substrates such as, for example, germanium wafers. In semiconductor processing, rapid thermal processing can be used as an annealing step to repair implant damage, improve the quality of the deposited layer, improve the quality of the interlayer interface, activate the dopant and achieve other purposes, while controlling the doping species at the same time. diffusion.

A strong and short exposure to light can be used to heat the entire top surface of the substrate at a rate of more than 10 ⁴ ° C per second to achieve millisecond (or ultra-fast) temperature processing of the semiconductor substrate. Rapid heating of only one surface of the substrate can result in a large temperature gradient across the thickness of the substrate while at the same time the substrate is mostly maintained at a temperature prior to illumination. Thus the majority of the substrate acts as a heat sink, resulting in a rapid cooling rate of the top surface.

The views and advantages of the specific embodiments of the present invention will be set forth in part in the description which follows.

An exemplary view of the present invention is a method of heat treating a substrate in a one millisecond annealing system. The method can include obtaining data indicative of a temperature distribution associated with one or more substrates during processing in a one millisecond annealing system. The millisecond annealing system can have a wafer plane plate that divides the processing chamber into a top processing chamber and a bottom processing chamber. The method can include adjusting the pressure within the processing chamber to cause temperature uniformity across one or more substrates.

Another exemplary aspect of the present invention is a method of heat treating a substrate in a one millisecond annealing system. The method can include obtaining data indicative of a temperature distribution associated with one or more substrates during processing in a one millisecond annealing system. The millisecond annealing system can have a wafer plane plate that divides the processing chamber into a top processing chamber and a bottom processing chamber. The method can include determining a shape and configuration of one or more of an edge reflector or a wedge reflector in the millisecond annealing system based at least in part on the temperature profile.

Yet another exemplary aspect of the present invention is a method of heat treating a substrate in a one millisecond annealing system. The method can include obtaining data indicative of a temperature distribution associated with one or more substrates during processing in a one millisecond annealing system. The millisecond annealing system can have a wafer plane plate to divide the processing chamber into a top processing Room and a bottom treatment room. The wafer plane plate can include a non-rotating substrate support. The method can include determining an angular position for placement of a device substrate within the processing chamber of the millisecond annealing system. The angular position can be determined at least in part by data showing the temperature distribution.

The demonstration views of this case may vary and be modified. Other exemplary aspects of the present disclosure are related to systems, methods, apparatus, and procedures for heat treating a semiconductor substrate.

These and other features, aspects, and advantages of the various embodiments will be apparent from the description and appended claims. The accompanying drawings, which are set forth in the claims,

60‧‧‧Semiconductor substrate

80‧‧ millisecond annealing system

[100]‧‧‧矽晶晶面

<110>‧‧‧lattice

150‧‧‧Temperature measurement system

152‧‧‧temperature sensor

154‧‧‧Temperature Sensor

158‧‧‧reference temperature sensor

160‧‧‧ processor circuit

200‧‧ millisecond annealing system

200‧‧‧Processing room

202‧‧‧ top processing room

204‧‧‧ bottom processing room

210‧‧‧ Wafer flat panel

212‧‧‧Support pin

220‧‧‧ top arc lamp

220‧‧‧Top lamp array

222‧‧‧ cathode

225‧‧‧Quartz tube

226‧‧‧ Plasma

228‧‧‧Water Wall

229‧‧‧ argon column

230‧‧‧Anode

232‧‧‧ tip

234‧‧‧heatsink

235‧‧‧Base

236‧‧‧Water cooling channel

240‧‧‧ bottom arc lamp

247.2‧‧‧Line profile

250‧‧ ‧ treatment room wall

252‧‧‧ top treatment room wall

254‧‧‧ bottom processing chamber wall

260‧‧‧Water Window

262‧‧‧ reflector

264‧‧‧Edge Reflector/Wedge Reflector

270‧‧‧Mirror

272‧‧‧Wedge reflector

274‧‧‧Reflecting element / wedge reflector

274.4‧‧‧Combined contour

276‧‧‧ grooves

282‧‧‧Inside slide

284‧‧‧ lateral slide

300‧‧‧Closed loop system

302‧‧‧Water/air inlet

304‧‧‧Argon/downstream pipeline

306‧‧‧Water/gas mixture

310‧‧‧Separator

315‧‧‧pressure sensor

320‧‧‧jet pump/controller

325‧‧‧ Valve

330‧‧‧ pump

340‧‧‧ coalescing filter

340‧‧‧Down exhaust duct

350‧‧‧Argon source/particle filter

350‧‧‧Particle filter

370‧‧‧Ion exchange filter

372‧‧‧ Valve

380‧‧‧Active carbon filter bypass circuit

390‧‧‧ heat exchanger

500‧‧‧Product Wafer

502‧‧‧ notch

510‧‧‧ representative map

520‧‧‧ cold spots

525‧‧‧ wafer edge

A detailed discussion of specific embodiments of those skilled in the art will be set forth in this specification, which is set forth with reference to the accompanying drawings in which: FIG. 1 illustrates an exemplary millisecond annealing heating curve in accordance with an exemplary embodiment of the present disclosure. 2 is an exploded perspective view of a portion of an exemplary millisecond annealing system in accordance with an exemplary embodiment of the present invention; and a third drawing is an exploded view of an exemplary millisecond annealing system in accordance with an exemplary embodiment of the present disclosure; The fourth drawing depicts a cross-sectional view of an exemplary millisecond annealing system in accordance with an exemplary embodiment of the present disclosure; 5 is a perspective view of an exemplary luminaire used in an exemplary millisecond annealing system in accordance with an exemplary embodiment of the present invention; and a sixth drawing depicts a wafer level of a millisecond annealing system in accordance with an exemplary embodiment of the present disclosure. A schematic diagram of an exemplary edge reflector used in a panel; a seventh diagram is a schematic diagram of an exemplary reflector that can be used in a one millisecond annealing system in accordance with an exemplary embodiment of the present invention; and the eighth figure depicts an example in accordance with the example of the present application. A schematic diagram of an exemplary arc lamp that can be used in a one millisecond annealing system of an embodiment; ninth through tenth drawings depict an operation diagram of an exemplary arc lamp according to an exemplary embodiment of the present invention; A cross-sectional view of an exemplary electrode of an exemplary embodiment of the present invention; a twelfth diagram is a schematic illustration of an exemplary closed loop system for supplying water and gas (eg, argon) to a specific embodiment in accordance with the present exemplary embodiment An example arc lamp used in a millisecond annealing system; a thirteenth diagram depicts an example of a one millisecond annealing system in accordance with an exemplary embodiment of the present disclosure A schematic diagram of a degree measuring system; a fourteenth drawing is a schematic diagram of an example airflow system for adjusting the pressure in a processing chamber of an exemplary millisecond annealing system in accordance with an exemplary embodiment of the present invention; A schematic diagram of a change shape of a water window in a one millisecond annealing system according to an exemplary embodiment of the present invention; The sixteenth drawing is a schematic diagram showing the changed shape of a water window in a one millisecond annealing system according to an exemplary embodiment of the present invention; and the seventeenth drawing is a schematic diagram of an exemplary product wafer, which has an array arrangement. A plurality of devices; an eighteenth drawing is a schematic diagram showing an example residual illumination unevenness of a wafer in a millisecond annealing system; and a nineteenth drawing is a drawing of a product wafer at different angles according to an exemplary embodiment of the present invention. A schematic diagram of a chamber interior; a twentieth diagram showing a schematic diagram of a product wafer placed at a different angle relative to a support pin in a processing chamber according to an exemplary embodiment of the present invention; A cross-sectional view showing the position of a top wedge reflector and an edge reflector in a processing chamber in a millisecond annealing system according to an exemplary embodiment; the twenty-second (a) and twenty-two (b) diagrams are drawn according to the example of the present invention DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A schematic diagram of an example top wedge having varying wedge angles; and twenty-third (a) and twenty-three (b) drawings depicting a top wedge wedge angle in accordance with an exemplary embodiment of the present disclosure A schematic diagram of an example illumination profile improvement; a twenty-fourth diagram depicting an exemplary edge reflector for use in a millisecond annealing processing chamber in accordance with an exemplary embodiment of the present invention; and a twenty-fifth diagram depicting a contour having a contour A schematic diagram of an example edge reflector; The twenty-sixth (a), twenty-sixth (b) and twenty-sixth (c) drawings depict schematic representations of various heated regions on a wafer by edge reflectors of varying shape and position in accordance with an exemplary embodiment of the present invention. .

Reference will now be made in detail to the particular embodiments embodiments The examples are presented to explain the specific embodiments and are not intended to be limiting. In fact, those skilled in the art should be able to see that the specific embodiments can be modified and varied without departing from the scope and spirit of the invention. For example, features illustrated or described as part of a particular embodiment can be used in conjunction with another embodiment to yield further embodiments. Therefore, the point of view in this case is to include such modifications and variations.

summary

An exemplary aspect of the present invention relates to a plurality of features across the temperature uniformity throughout a substrate (e.g., a semiconductor wafer) during processing in a one millisecond annealing system. The discussion of this point of view is based on a "wafer" or semiconductor wafer for illustration and discussion purposes. Those of ordinary skill in the art will appreciate that the exemplary aspects of the present disclosure can be used in conjunction with any workpiece, semiconductor substrate, or other suitable substrate, using the disclosure provided herein. The word "about" is used in conjunction with a numerical value to mean within 10% of the stated value.

A strong and short illumination can be used to heat the entire top surface of the substrate at a rate of more than about 10 ⁴ ° C per second to achieve millisecond (or ultra-fast) temperature processing of the semiconductor substrate. The flash is typically applied to a semiconductor substrate that is heated to an intermediate temperature Ti at a ramp rate of up to 150 ° C per second. After the heating step, the semiconductor substrate is left in the processing chamber for cooling. Both the low warming process and the cooling can cause a lateral temperature differential resulting in a non-uniform temperature distribution across the substrate. In many instances, heat treatment applications are temperature sensitive. In addition, wafer stress can be driven by thermal gradients within the wafer material. Large lateral thermal gradients can thus cause wafer warpage, slippage, and even wafer breakage.

The main reason for the temperature difference during heat treatment is the uneven illumination of the wafer by the light source. The main reason for the temperature difference during cooling can be caused by the shape of the wafer itself. For example, the wafer can be dished, and due to its shape, the edge of the wafer will cool faster than the center of the wafer. Another cause of the temperature difference can be caused by convective cooling of the surrounding gas.

Inhomogeneities can be mitigated by using highly reflective mirrors. For example, the illumination unevenness can be mitigated by an integrating effect of a cube having a mirror wall. Cooling non-uniformity can be mitigated by redirecting the emitted light from the center of the wafer to reabsorb the edge of the wafer. In the same way, this can be achieved by the integration of a cube with a mirror wall.

Even though the processing chamber in the millisecond annealing system can utilize the integration of the mirror walls, there is still a residual non-uniformity that needs to be further compensated. The main influence factor that compensates for residual inhomogeneities can be controlled by manipulating the illumination distribution.

In accordance with an exemplary embodiment of the present disclosure, various features are disclosed for improving the temperature uniformity of a semiconductor substrate during processing in a one millisecond annealing system Sign. For example, these features may include: (1) changing the pressure inside the processing chamber of the millisecond annealing system; (2) manipulating the illumination distribution by the refraction effect of a water window in the millisecond annealing system; (3) the angle of the wafer Position; and/or (4) configure the shape and/or position of the reflector used in the millisecond annealing system.

An exemplary embodiment of the present invention is directed to a method of heat treating a substrate in a one millisecond annealing system. The method includes obtaining data indicative of a temperature distribution associated with one or more substrates during processing in a one millisecond annealing system. The millisecond annealing system includes a wafer planar plate that divides the processing chamber into a top processing chamber and a bottom processing chamber. The method includes adjusting a pressure inside the processing chamber based at least in part on the data indicative of the temperature distribution to cause temperature uniformity across the one or more substrates. For example, in some embodiments, adjusting the pressure comprises: adjusting a pressure within the processing chamber during processing of at least one of the one or more substrates to adjust at least one of the one or more substrates Temperature distribution. For example, the pressure can be adjusted over a range of values from +2 kPA to -2 kPA relative to atmospheric pressure.

In some embodiments, adjusting the pressure in the process chamber includes adjusting a pressure differential between the process chamber and a downstream line of the gas flow system configured to process gas flow through the process chamber. The downstream line may be located downstream of one or more exhaust ports in the process chamber. Adjusting the differential pressure can include adjusting a valve placed in the downstream line. The valve can be adjusted by one or more controllers based on one or more signals from a pressure sensor configured to measure the pressure within the processing chamber. This pressure can be adjusted to affect the process gas flow pattern within the process chamber.

In some embodiments, adjusting the pressure within the processing chamber includes warping a water window based on the pressure within the processing chamber. The water window may include an inner panel and an outer panel, and water flows between the inner panel and the outer panel. The inner panel is placed closer to the processing chamber relative to the outer panel. In some embodiments, the water window can be warped such that the inner panel of the water window is bent away from the processing chamber to provide a defocusing effect on the light. In some embodiments, the water window can be warped such that the inner panel of the water window is bent toward the processing chamber to provide a focusing effect on the light.

Another exemplary embodiment of the present invention is directed to a method of heat treating a substrate in a one millisecond annealing system. The method includes obtaining data indicative of a temperature distribution associated with one or more substrates during processing in a one millisecond annealing system. The millisecond annealing system can include a wafer planar plate that divides the processing chamber into a top processing chamber and a bottom processing chamber. The method can include adjusting a shape, configuration, or position of one or more of an edge reflector or a wedge reflector within the millisecond annealing system based at least in part on the temperature profile.

In some embodiments, the wedge reflector can be placed on a processing chamber wall adjacent to the wafer plane plate. Adjusting the shape, configuration or position of one or more of an edge reflector or a wedge reflector within the millisecond annealing system includes adjusting a wedge angle and/or the height of the wedge reflector.

In some embodiments, the edge reflector is placed within the wafer plane plate. Adjusting the shape, configuration or position of one or more of an edge reflector or a wedge reflector in a millisecond annealing system includes adjusting a surface profile for the edge reflector. In some embodiments, adjusting an edge reflector in a millisecond annealing system or The shape, configuration or location of one or more of the wedge reflectors includes adjusting (in one or more controllers) the position of the wedge reflector relative to the substrate during processing of the substrate.

Another exemplary embodiment of the present invention is directed to a method of heat treating a substrate in a one millisecond annealing system. The method includes obtaining data indicative of a temperature distribution associated with one or more substrates during processing in a one millisecond annealing system. The millisecond annealing system can include a wafer planar plate that divides the processing chamber into a top processing chamber and a bottom processing chamber. The method can include determining an angular position for placement of a device substrate within a processing chamber of the millisecond annealing system. The angular position can be determined based at least in part on the temperature profile. In some embodiments, the angular position can be determined based at least in part on the position of one or more support pins in the millisecond annealing system.

Example millisecond annealing system

An exemplary millisecond annealing system can be configured to provide a strong and short exposure to light to heat the top surface of a wafer at a rate that exceeds (e.g.,) about 10 ⁴ ° C/s. An exemplary temperature profile (100) of a semiconductor substrate depicted in the first figure is accomplished using a one millisecond annealing system. As shown in the first figure, during a ramp up phase (102), most of the semiconductor substrate (e.g., a wafer) is heated to an intermediate temperature Ti. The intermediate temperature can be in the range of from about 450 °C to about 900 °C. When the intermediate temperature Ti has been reached, the top surface of the semiconductor substrate can be exposed to a very brief intense flash, resulting in a heating rate of up to about 10 ⁴ ° C per second. A window (110) plots the temperature distribution of the semiconductor substrate during the short, strong flash. Curve (112) represents the rapid heating of the top surface of the semiconductor substrate during flash exposure. Curve (116) plots the temperature of the remainder or most of the semiconductor substrate during flash exposure. The curve (114) represents the top surface cooling of the semiconductor substrate by conduction rapid cooling, which is caused by the majority of the semiconductor substrate acting as a heat sink. Most of the semiconductor substrate acts as a heat sink, creating a high top surface cooling rate for the substrate. Curve (104) represents the slow cooling of most semiconductor substrates by thermal radiation and convection with a process gas as the coolant. In this paper, the word "about" is used with reference to a numerical value and refers to within 30% of the proposed value.

An exemplary millisecond annealing system can include a plurality of arc lamps (e.g., four argon arc lamps) as a source of intense millisecond long exposure (so-called "flash") on the top surface of the semiconductor substrate. When the substrate has been heated to an intermediate temperature (for example, about 450 ° C to about 900 ° C), the flash can be applied to the semiconductor substrate. A plurality of continuous mode arc lamps (e.g., two argon arc lamps) can be used to heat the semiconductor substrate to the intermediate temperature. In some embodiments, the semiconductor substrate is heated to an intermediate temperature that is transmitted through the bottom surface of the semiconductor substrate to heat the ramp rate of the majority of the wafer.

The second through fifth figures depict a representation of various aspects of an exemplary millisecond annealing system (80) in accordance with an exemplary embodiment of the present invention. As shown in the second through fourth figures, the one millisecond annealing system (80) can include a processing chamber (200). The processing chamber (200) can be separated into a top processing chamber (202) and a bottom processing chamber (204) by a wafer plane plate (210). A semiconductor substrate (60) (eg, a germanium wafer) may be mounted to a wafer support plate (214) (eg, quartz glass inserted into the wafer planar plate (210)) A support pin (212) of the plate) (for example, a quartz support pin) is supported.

As shown in the second and fourth figures, the millisecond annealing system (80) can include a plurality of arc lamps (220) (eg, four argon arc lamps) placed adjacent to the top processing chamber (202) for use as A light source with a strong millisecond long exposure (so-called "flash") on the top surface of the semiconductor substrate (60). When the substrate has been heated to an intermediate temperature (for example, about 450 ° C to about 900 ° C), the flash can be applied to the semiconductor substrate.

A plurality of continuous mode arc lamps (240) placed adjacent to the bottom processing chamber (204) (e.g., two argon orphan lamps) can be used to heat the semiconductor substrate (60) to the intermediate temperature. In some embodiments, the heating of the semiconductor substrate (60) to an intermediate temperature is achieved from the bottom processing chamber (204) via the bottom surface of the semiconductor substrate (60) to increase the ramp rate of the entire volume of the wafer.

As shown in the third figure, from the bottom arc lamp (240) (for example, for heating the semiconductor substrate to an intermediate temperature), and the top arc lamp (220) (for example, for providing millisecond heating by flash) Light that heats the semiconductor substrate (60) can enter the processing chamber (200) through a water window (260) (eg, a water-cooled quartz glass window). In some embodiments, the water window (260) may comprise a sandwich construction having an aqueous layer of about 4 mm thick between the two quartz glass sheets to cool the quartz sheet and, for example, a wavelength of about 1400 nm or more. A filter is provided.

As further depicted in the third figure, the process chamber wall (250) can include a mirror (270) for reflecting the heated light. For example, the mirror (270) can be a water cooled, polished aluminum sheet. In some embodiments, the body of the arc lamp used in the millisecond annealing system can include a reflector for luminaire radiation. For example That is, the perspective view of the fifth diagram simultaneously depicts both the top lamp array (220) and the bottom lamp array (240) that can be used in the millisecond annealing system (200). As shown in the figures, the bodies of each of the arrays of lamps (220) and (240) may include a reflector (262) for reflecting the heated light. These reflectors (262) may form a portion of the reflective surface of the processing chamber (200) of the millisecond annealing system (80).

The temperature uniformity of the semiconductor substrate can be controlled by manipulating the light intensity falling in different regions of the semiconductor substrate. In some embodiments, uniformity control can be achieved by varying the number of reflection stages of the small reflector to the primary reflector and/or by using edge reflections mounted on the wafer support plate surrounding the crystal. The machine is reached.

For example, an edge reflector can be used to redirect light from the bottom luminaire (240) to the edge of the semiconductor substrate (60). As an example, the sixth figure depicts an example edge reflector (264) that forms a portion of the wafer planar plate (210) that can be used to direct light from the bottom luminaire (240) to the edge of the semiconductor substrate (60). An edge reflector (264) can be mounted to the wafer planar panel (210) and can surround or at least partially surround the semiconductor substrate (60).

In some embodiments, additional reflectors can also be mounted to the processing chamber wall adjacent to the wafer plane plate (210). For example, the seventh figure depicts an example reflector that can be mounted to the wall of the processing chamber as a mirror for heating the light. More specifically, the seventh figure shows an example wedge reflector (272) mounted to the bottom processing chamber wall (254). The seventh diagram also depicts a reflective element (274) mounted to the reflector (270) of a processing chamber wall (252). Where the semiconductor substrate (60) is Uniformity can be adjusted by varying the number of reflection stages of the wedge reflector (272) within the processing chamber (200) and/or other reflective elements (e.g., reflective element (274)).

The various faces of the example top arc lamp (220) depicted in Figures 8 through 11 can be used as a source of intense millisecond long exposure of the top surface of the semiconductor substrate (60) (e.g., "flash") . For example, the eighth figure depicts a cross-sectional view of an example arc lamp (220). For example, the arc lamp (220) can be a smooth arc lamp in which pressurized argon (or other suitable gas) is converted to high pressure plasma during an arc discharge. Arcing occurs between a negatively charged cathode (222) in a quartz tube (225) and a spaced positively charged anode (230) (e.g., about 300 mm apart). Once the voltage between the cathode (222) and the anode (230) reaches a breakdown voltage of argon or other suitable gas (eg, about 30 kV), a stable, low-induction plasma is formed that emits visible light in the electromagnetic spectrum. Light in the ultraviolet range. As shown in the ninth figure, the luminaire can include a lamp reflector (262) that can be used to reflect the light provided by the luminaire for processing by the semiconductor substrate (60).

Tenth and eleventh views depict aspects of an example operation of an arc lamp (220) in accordance with an exemplary millisecond annealing system (80) in accordance with an exemplary embodiment of the present disclosure. More specifically, a plasma (226) is contained within a quartz tube (225) that is water cooled by a water wall (228) from the inside. The water wall (228) is injected at a high flow rate at the cathode end of the luminaire (200) and discharged at the anode end. The same is true for argon (229), which enters the luminaire (220) at the cathode end and exits from the anode end. Forming a water wall (228) The water is injected into the vertical lamp shaft so that the centrifugal force produces a water vortex. Therefore, a channel is formed along the center line of the luminaire for use with argon (229). The argon column (229) rotates in the same direction as the water wall (228). Once the plasma (226) is formed, the water wall (228) protects the quartz tube (225) and traps the plasma (226) to the central axis. Only the water wall (228) and the electrodes (cathode (230) and anode (222)) are in direct contact with the high energy plasma (226).

An eleventh drawing depicts a cross-sectional view of an example electrode (e.g., cathode (230)) for use with an arc lamp in accordance with an exemplary embodiment of the present invention. Figure 11 depicts a cathode (230). However a similar configuration can be used for the anode (222).

In some embodiments, one or more of the electrodes may each include a tip (232) as the electrode experiences a high thermal load. The tip can be made of tungsten. The tip can be coupled to and/or melted to a water cooled copper heat sink (234). The copper heat sink (234) can include at least a portion of the internal cooling system of the electrodes (eg, one or more water cooling channels (236)). The electrode may further comprise a brass base (235) having a water cooling passage (236) for circulating water or other liquid and cooling the electrode.

An arc lamp for use in an exemplary millisecond annealing system in accordance with the teachings of the present invention may be an open flow system for water and argon. However, for maintenance, in some embodiments both media may be circulated in a closed loop.

A twelfth diagram depicts an exemplary closed loop system (300) for supplying water and argon, which is required for operation of an open flow argon arc lamp used in the millisecond annealing system of the exemplary embodiment of the present invention.

More specifically, high purity water (302) and argon (304) are injected into the luminaire (220). High purity water (302) is used for water wall and electrode cooling. Leaving the luminaire is a gas/water mixture (306). The water/gas mixture (306) is separated into a gas-free water (302) and a dry argon (304) by a separator (310) before being reinjected into the inlet of the luminaire (220). To produce the desired pressure drop across the luminaire (220), the gas/water mixture (306) is pressurized by a water driven jet pump (320).

A high power electric pump (330) supplies water pressure to drive the water wall within the luminaire (220), the cooling water for the luminaire electrodes, and the drive flow for the jet pump (320). A separator (310) downstream of the jet pump (320) can be used to extract the liquid phase and gas phase (argon) from the mixture. Prior to re-entering the luminaire (220), the argon is further dried in a coalescing filter (340). Additional argon gas may be supplied from the argon source (350) if desired.

The water system passes through one or more particulate filters (350) to remove particles that are splashed into the water by the arc. Ionic contaminants are removed by ion exchange resins. A portion of the water flows through the mixed bed ion exchange filter (370). The water inlet valve (372) leading to the ion exchange bypass (370) can be controlled by the resistivity of the water. If the resistivity of the water drops below a lower value, the valve (372) is opened and if it reaches a higher value the valve (372) is closed. The system can include an activated carbon filter bypass circuit (380) where a portion of the water can be additionally filtered to remove organic contaminants. To maintain water temperature, water can pass through a heat exchanger (390).

A millisecond annealing system in accordance with an exemplary embodiment of the present disclosure may include the ability to independently measure the temperature of both surfaces (e.g., top and bottom). thirteenth The figure depicts an example temperature measurement system (150) for a millisecond annealing system (200).

Shown in the thirteenth figure is a simplified representation of the millisecond annealing system (200). The temperature of both surfaces of the semiconductor substrate (60) can be independently measured by a temperature sensor such as a temperature sensor (152) and a temperature sensor (154). A temperature sensor (152) measures the temperature of a top surface of the semiconductor substrate (60). The temperature sensor (154) measures the temperature of a bottom surface of the semiconductor substrate (60). In some embodiments, a narrow pyrometer sensor measuring a wavelength of about 1400 nm can be used as a temperature sensor (152) and/or (154) to measure (eg, like) the center of a semiconductor substrate (60). The temperature of the area. In some embodiments, the temperature sensors (152) and (154) may be ultrafast radiometers (UFR) having a sufficiently fast sampling rate to resolve millisecond temperature peaks caused by flash heating.

The readings of temperature sensors (152) and (154) can be compensated for by emissivity. As shown in FIG. 13, the emissivity compensation architecture can include a debug flash (156), a reference temperature sensor (158), and a temperature sensor configured to measure the top and bottom surfaces of the semiconductor wafer. (152) and (154). Debug heating and measurement can be used with a debug flash (156) (for example, a test flash). Measurements from the reference temperature sensor (158) can be used as emissivity compensation for the temperature sensors (152) and (154).

In some embodiments, the millisecond annealing system (200) can include a water window. The water window can provide a filter that suppresses luminaire radiation in the measurement band of temperature sensors (152) and (154) such that temperature sensors (152) and (154) only measure from the semiconductor substrate. Radiation.

The readings of temperature sensors (152) and (154) can be provided to a processor circuit (160). The processor circuit (160) can be placed within the housing of the millisecond annealing system (200), although alternatively the processor circuit (160) can be placed away from the millisecond annealing system (200). The various functions described herein can be implemented by a single processor circuit, or by other combinations of local and/or remote processor circuits, if desired.

The readings of temperature sensors (152) and (154) can be used by processor circuit (160) to determine the temperature distribution across the substrate. This temperature profile provides temperature measurements of the substrate at various locations across the surface of the substrate. The temperature profile provides a measure of the thermal uniformity of the substrate during processing. As detailed later, data showing temperature distribution can be used to improve thermal uniformity by: (1) changing the pressure inside the processing chamber of the millisecond annealing system; and (2) annealing the system by milliseconds. The refractive effect of the window, manipulating the illumination distribution; (3) the angular position of the wafer; and/or (4) configuring the shape and/or position of the reflector used in the millisecond annealing system.

Example uniformity improvement through process chamber pressure control

According to an exemplary aspect of the present invention, the temperature uniformity of a semiconductor substrate during processing in a one millisecond annealing system can be improved by changing the pressure within the processing chamber. The pressure in the processing chamber can affect the processing gas flow pattern in the processing chamber and change the convective cooling distribution in different regions of the wafer.

The processing chamber within the millisecond annealing system can operate at atmospheric pressure. The processing chamber can be sealed to the ambient atmosphere to achieve an ultra-pure gas around the processing chamber. The pressure in the processing chamber can be determined by the mechanical stability of the quartz plate of the water window. Corrected within the limits. For example, the allowable pressure range may be from about +2 kPa to about -2 kPa based on atmospheric pressure.

For example, in some embodiments, a method of heat treating a substrate in a one millisecond annealing system can include obtaining data indicative of a temperature distribution associated with one or more substrates during a one millisecond annealing system process. The temperature profile provides a measure of the thermal uniformity of the substrate during processing. The temperature profile provides the temperature at various points on the substrate. Data showing the temperature distribution of one or more substrates can be analyzed to determine any non-uniformity in temperature distribution during processing. To address non-uniformities, the pressure within the processing chamber can be adjusted to result in temperature uniformity across one or more substrates.

In some embodiments, data showing the temperature distribution of a substrate during processing can be obtained. The unevenness identified in the temperature profile can trigger pressure adjustment during processing of the semiconductor substrate. As such, a closed loop pressure control based on the measured temperature profile can be used to adjust the temperature uniformity of a wafer during processing.

The fourteenth drawing depicts a diagram of an example airflow system for adjusting the pressure within a processing chamber (200) of an exemplary millisecond annealing system in accordance with an exemplary embodiment of the present invention. The processing chamber (200) can be a flow system in which the process gas system continuously enters the process chamber from the air inlet (302) via an air inlet port located at a top corner of the processing chamber (200). The process gas may exit the process chamber (200) via an exhaust port located at a bottom corner of the process chamber. Downstream of the exhaust port, the four exhaust pipes can be combined into a single downstream line (304). The downstream pipeline (304) can be connected Connected to a downstream exhaust conduit (340). The downstream exhaust conduit (340) provides a pressure differential P? relative to the processing chamber necessary to discharge the process gas from the process chamber. By varying the differential pressure P?, the pressure within the process chamber can be adjusted.

In some embodiments, the differential pressure PΔ can be adjusted by a controller (320). The controller (320) can be any suitable control device, such as, for example, one or more processor circuits, executing computer readable instructions stored in one or more memory devices. A control variable for the controller (320) may be a pressure sensor (315) mounted to the processing chamber. A pressure sensor (315) can measure the pressure within the processing chamber (200) and can transmit a signal indicative of the pressure to the controller (320) via an appropriate communication medium.

The actuator of the controller (320) may be a valve (325) (e.g., a butterfly valve) located within the exhaust manifold that changes the airflow resistance and thus changes the differential pressure of the downstream line (304). Low airflow resistance reduces process chamber pressure. High airflow resistance increases chamber pressure. The pressure set point for the controller (320) can be defined by a user, for example, based on a temperature profile across the substrate. The controller (320) can be configured to control the pressure based on the signal from the pressure sensor to achieve the pressure set point. In some embodiments, the differential pressure can be adjusted by passive mechanical restriction (e.g., a restriction, damper or baffle) or by setting the pressure of the external exhaust line.

The pressure in the processing chamber can affect the flow pattern of the process gas in the processing chamber. Thus, by adjusting the pressure within the process chamber in accordance with an exemplary embodiment of the present invention, the convective cooling profile of different regions on the wafer can be adjusted.

Adjusting the pressure also affects the illumination distribution of the light provided through the water window in the millisecond annealing system. For example, in some embodiments, the temperature uniformity of a semiconductor substrate during processing in a millisecond annealing system can be improved by adjusting the illumination distribution in accordance with the refractive effect of the water window used in the millisecond annealing system. A water window is a plane-parallel slide in its normal state, having the following stacking order: (1) quartz; (2) water; (3) quartz. Water can flow through the interlayer of the two quartz sheets. Warping the stack can cause the water window to act as the same lens, allowing the light to pass through the water window and adjust the illumination distribution through the water window.

In some embodiments, the warpage of the water window can be achieved by increasing or decreasing the pressure within the processing chamber. As discussed above, the pressure within the processing chamber can be corrected within the limits defined by the mechanical stability of the quartz crystal of the water window. For example, the allowable pressure range may be from about +2 kPa to about -2 kPa based on atmospheric pressure. Since the cooling water flowing in the water window is at a steady pressure very close to atmospheric pressure, the pressure change in the processing chamber affects the inner quartz piece of the water window. This causes a change in the thickness from the center to the edge of the water layer.

More specifically, fifteenth and sixteenth drawings depict a water window (260) having an inner slide (282) and an outer slide (284). The inner slide (282) and the outer slide (284) may be made of, for example, quartz. Water can flow between the inner slide (282) and the outer slide (284). The inner slide (282) can be placed closer to the processing chamber of the millisecond annealing system relative to the outer slide (284).

As shown in Fig. 15, the inner slide (282) of the water window (260) is bent outward (e.g., away from the processing chamber) at a relatively atmospheric pressure of the positive chamber pressure. A convex water layer that has a defocusing effect on light. As shown in Fig. 16, the inner slide (282) of the water window (260) is bent inward (e.g., toward the processing chamber) at a relatively atmospheric pressure negative chamber pressure, resulting in a convex surface having a focusing effect on the light. Water layer.

Example uniformity improvement achieved by wafer angular position

According to an exemplary aspect of the present disclosure, temperature uniformity during processing in a millisecond annealing system with a layout pattern device wafer (e.g., a product wafer) can be improved by angular wafer positioning. A product wafer can sometimes contain hundreds of dies arranged in an array on the front surface of the wafer.

For example, a seventeenth diagram depicts a diagram of an example product wafer (500) having a plurality of devices arranged in an array. Since germanium is a crystal, the grains can be oriented along the major axis of the crystal lattice. Most commonly, the wafer surface is cut along the twin plane [110]. The wafer has a notch (502) indicating the orientation of the lattice <110>. The grain arrangement results in a laterally varying light absorption capability. Thus, the die array adds uneven light absorption characteristics to the wafer surface.

Figure 18 depicts a representative map (510) which is an illustration of an example residual non-uniformity of illumination of a wafer in a millisecond annealing system. As shown in Figure 18, the process chamber can have a residual, inherent illumination non-uniformity that results in side-to-wafer temperature non-uniformities. This inherent illumination non-uniformity can be due, for example, to luminaire orientation, reflector position, and other components of the millisecond annealing system.

According to the millisecond annealing system of the present example, a fixed, non-rotating wafer support configuration can be used. Therefore, the angle wafer orientation can be used Optimizing or improving temperature uniformity is achieved by at least partial alignment depending on the illumination mode inherent to the processing chamber.

More specifically, in some embodiments, the method of heat treating a substrate in a one millisecond annealing system can include obtaining data indicative of a temperature distribution associated with one or more substrates during a one millisecond annealing system process. Data showing the temperature distribution of one or more substrates can be analyzed to determine any temperature distribution non-uniformity during processing. To address non-uniformities, the angular positioning of one or more wafers within the processing chamber can be adjusted to achieve temperature uniformity across the one or more substrates.

A nineteenth drawing depicts a pattern of a product wafer (500) in a processing chamber (200). As shown in the figure, the wafer (500) can be placed at a different angle relative to the processing chamber and relative to the luminaire. In the example of the nineteenth figure, the wafer (500) is placed such that its notch (502) is at the notch alignment angle θ. Thus, the interaction between the absorption pattern and the illumination pattern can be enhanced by adjusting the angular orientation of the wafer (500).

In some embodiments, the product wafers can be aligned via the notches before being placed in the loading and unloading system of the millisecond annealing system. The notch alignment angle θ determines the angular orientation within the processing chamber. Wafer orientation can be measured based on the position of the notch relative to the process chamber spindle (eg, given by the wall). In other embodiments, the notch alignment can be performed within the processing chamber, for example, by a notch alignment station or by a notch aligner integrated into an automaton.

In some embodiments, the wafer can be mounted to a wafer support plate. The quartz pin is supported. The number of support pins used to support the wafer can vary from three to six or more. A common wafer support architecture uses four support pins arranged in a square equidistant from the center of the wafer. In general, the support pin can cause a partial cold spot. Moreover, the support pin can induce a mechanical stress mode. By the angular orientation of the wafer relative to the support pins, the negative impact of the support pins can be moved to areas that are more beneficial to the wafer. Moreover, by shifting the contact point away from the main lattice axis, wafer stress can be mitigated.

For example, the twentieth diagram depicts a diagram of a wafer (500) within the processing chamber (200) showing the position of the support pin (212) relative to the wafer (500). The orientation of the wafer (500) relative to the support pin (212) can reduce the effect of the support pin (212) by placing the support pin (212) at a different location relative to the wafer (500).

Improve uniformity by shape and position of the reflector

In accordance with an exemplary embodiment of the present disclosure, temperature uniformity during processing of a semiconductor substrate in a one millisecond annealing system may be improved in part by the shape of one or more reflectors within the millisecond annealing system processing chamber. For example, a top wedge reflector and/or one or more edge reflectors can have a shape and/or configuration that is designed to improve thermal uniformity. Small sized reflectors can be used to reduce residual non-uniformities in the processing chamber in a millisecond annealing system.

In some embodiments, a method of heat treating a substrate in a one millisecond annealing system can include obtaining data indicative of a temperature distribution associated with one or more substrates during a one millisecond annealing system process. Display one or more substrates The temperature distribution data can be analyzed to determine any temperature distribution non-uniformity during processing. To address non-uniformities, the shape, configuration, and/or position of one or more wafers within the processing chamber can be adjusted to achieve temperature uniformity across the one or more substrates.

The twenty-first figure depicts a cross-sectional view of a one millisecond annealing system showing the position of the top wedge reflector (274) and edge reflector (264) in the processing chamber within the millisecond annealing system. A top wedge reflector (274) can be placed on the wall of the processing chamber adjacent to the wafer plane. The top wedge reflector (274) can be wedge shaped. The edge reflector (264) can be placed on the wafer plane and can surround a substrate during processing.

In some embodiments, there may be two top wedge reflectors (264) placed on the wall of the processing chamber in the top processing chamber of a processing chamber of the millisecond annealing system. The top edge reflector (264) can be used to control the illumination distribution perpendicular to the main axis of the fixture. In some embodiments, the wedge reflector (264) can be mounted in the upper half of the processing chamber along the bottom edge of the lens facing the door and facing the rear end of the processing chamber.

Generally, the wafer temperature distribution has a cold zone at the edge of the wafer perpendicular to the orientation of the luminaire. The size and strength of these cold spots can be affected by the wedge reflector (264). The millisecond annealing system can have the ability to individually excite the flash release of each of the top luminaires. This ability is primarily used to shape the time-temperature profile of a flash event. This ability has the side effect that the illumination pattern changes locally over time, due to the fact that the top luminaire is at a different location relative to the wafer. This can have an effect on the size of the cold spot on the edge of the wafer, depending on the firing order of the luminaire. These effects can be compensated for by using a wedge with an optimized angle.

The twenty-second figure depicts a diagram of an example top wedge reflector (264) having varying wedge angles. More specifically, the twenty-second (a) diagram depicts a top wedge reflector (264) having a wedge angle of 0°. Figure 22 (b) depicts a top wedge reflector with a 10° wedge angle. By varying the wedge angle, the amount of light that strikes the edge region can be controlled. In some embodiments, the wedge reflector (264) can be mounted to a motor or other mechanical device that can be configured to adjust the wedge angle and/or position of the wedge reflector (264). For example, the controller can respond to temperature measurements of the substrate in real time, adjusting the wedge reflector wedge angle to provide more uniform processing.

In some embodiments, the wedge angle can be preset by cutting the parts. Optimization of uniformity can be implemented by mounting a suitable wedge having a selected wedge angle to the processing chamber. In other embodiments, the wedge angle can be set by skewing the wedge with a spacer or by a set screw. In some embodiments, the illumination profile is manipulated by additionally varying the wedge height and the wedge reflectivity.

The twenty-third figure plots an example of an improved illumination distribution by adjusting the wedge angle of the top wedge from a 5 wedge angle to a 1 wedge angle. More specifically, the twenty-third (a) diagram depicts the temperature profile of a wafer processed in a processing chamber having a plurality of top wedge reflectors having a 5° wedge angle. As shown in the figure, the wafer may have a cold spot (520) at the edge of the wafer due to the reduced illumination. Twenty-third (b) is a diagram depicting the temperature profile of a wafer processed in a processing chamber having a plurality of top wedge reflectors having a 1° wedge angle. As shown As shown, the temperature of the wafer edge (525) is more uniform and the occurrence of cold spots has been reduced.

Another method of manipulating the amount of illumination at the edge of the wafer is by the position, shape, and reflectivity of the edge reflector (274). The twenty-fourth drawing depicts a perspective view of four edge reflectors (274) used in the processing chamber. An edge reflector (274) redirects light from the bottom fixture to the edge of the wafer. The reflectivity of the edge reflector (274) can be modified by cutting the notch (276) into the reflective plane. The ratio of the groove area to the area of the remaining reflector is determined by the amount of reflectivity.

The twenty-fifth diagram depicts a straight line profile using a standard edge reflector (274) in a millisecond annealing system. In accordance with an exemplary embodiment of the present disclosure, temperature uniformity of a wafer can be corrected by linearly converting the contour shape to a parabola or a combination thereof, and/or by relative position of the wafer. This approach determines the size and location of the heated edge of the wafer edge.

More specifically, the twenty-sixth (a) diagram depicts light reflection from a substrate (60) by an edge reflector (274) having a linear profile (274.2). Twenty-sixth (b) depicts light reflection from a substrate (60) by an edge reflector (274) having a parabolic and linear contour combination (274.4). Figure 26 (c) depicts light reflection from a substrate (60) by an edge reflector (274) having a parabolic and linear contour combination (274.4), but having an adjusted relative to the substrate position.

In some embodiments, the edge reflector (274) can be mounted to a motor or other mechanical device that can be configured to adjust the position and/or surface profile of the edge reflector. For example, the controller can respond to the temperature of the substrate in real time. The measured value adjusts the position of one or more edge reflectors to provide a more uniform process.

Although the present invention has been described in detail with reference to the specific exemplary embodiments thereof, it should be understood that those skilled in the art can readily adapt, change, and Produce an equivalent. Therefore, the disclosure of the present invention is intended to be illustrative only and not limiting, and the subject matter of the present disclosure does not exclude such modifications, variations and/or modifications of the inventions which are readily apparent to those skilled in the art. Addition and so on.

200‧‧‧Processing room

300‧‧‧Closed loop system

302‧‧‧air inlet

304‧‧‧Downstream pipeline

315‧‧‧pressure sensor

320‧‧‧ Controller

325‧‧‧ Valve

340‧‧‧Down exhaust duct

Claims (20)

A method of heat treating a substrate in a one millisecond annealing system, comprising: obtaining data indicative of a temperature distribution associated with one or more substrates during a one millisecond annealing system process, the millisecond annealing system having a wafer planar plate, The processing chamber is divided into a top processing chamber and a bottom processing chamber; and the pressure inside the processing chamber is adjusted based at least in part on the data indicative of the temperature distribution to cause temperature uniformity across the one or more substrates. The method of claim 1, wherein adjusting the pressure comprises adjusting a pressure within the processing chamber during processing of at least one of the one or more substrates to adjust at least one of the one or more substrates Temperature Distribution. The method of claim 1, wherein the pressure is adjusted within a range of from about +2 kPA to about -2 kPA relative to atmospheric pressure. The method of claim 1, wherein the adjusting the pressure in the processing chamber comprises adjusting a pressure difference between the processing chamber and a downstream line of the airflow system configured to flow the processing gas through the processing chamber, the downstream pipeline position Downstream of one or more exhaust ports within the processing chamber. The method of claim 4, wherein adjusting the differential pressure comprises adjusting a valve placed in the downstream line. The method of claim 5, wherein the valve is adjusted by one or more controllers based on one or more signals from a pressure sensor configured to measure pressure within the processing chamber. The method of claim 1, wherein the pressure is adjusted to affect a flow pattern of a process gas within the processing chamber. The method of claim 1, wherein adjusting the pressure in the processing chamber comprises warping a water window according to the pressure in the processing chamber. The method of claim 8, wherein the water window comprises an inner slide and an outer slide having water flowing between the inner slide and the outer slide, the inner slide being relative to the The outer slide is placed closer to the processing chamber. The method of claim 9, wherein the water window is warped such that the inner slide of the water window is bent away from the processing chamber to provide a defocusing effect on the light. The method of claim 9, wherein the water window is warped such that the inner slide of the water window is bent toward the processing chamber to provide a focusing effect on the light. A method of heat treating a substrate in a one millisecond annealing system, comprising: obtaining data indicative of a temperature distribution associated with one or more substrates during a one millisecond annealing system process, the millisecond annealing system having a wafer planar plate, The processing chamber is divided into a top processing chamber and a bottom processing chamber; the shape, configuration or position of one or more of an edge reflector or a wedge reflector in the millisecond annealing system is adjusted based at least in part on the temperature profile. The method of claim 12, wherein the wedge reflector is placed on a wall of a processing chamber adjacent to the planar panel of the wafer. The method of claim 13, wherein adjusting the shape, configuration or position of one or more of an edge reflector or a wedge reflector in the millisecond annealing system comprises adjusting a wedge angle for the wedge reflector . The method of claim 13, wherein adjusting the shape, configuration or position of one or more of an edge reflector or a wedge reflector in the millisecond annealing system comprises adjusting a height for the wedge reflector. The method of claim 13, wherein the edge reflector is placed in the wafer plane plate. The method of claim 12, wherein adjusting the shape, configuration or position of one or more of an edge reflector or a wedge reflector in the millisecond annealing system comprises adjusting a surface profile for the edge reflector . The method of claim 12, wherein adjusting the shape, configuration or position of one or more of an edge reflector or a wedge reflector in the millisecond annealing system is included in one or more controls during processing of the substrate And adjusting the position of the wedge reflector relative to the substrate. A method of heat treating a substrate in a one millisecond annealing system, comprising: obtaining data indicative of a temperature distribution associated with one or more substrates during a one millisecond annealing system process, the millisecond annealing system having a wafer planar plate, Dividing the processing chamber into a top processing chamber and a bottom processing chamber, the wafer flat panel comprising a non-rotating substrate support; determining an angular position for placement of a device substrate in a processing chamber of the millisecond annealing system, The angular position is determined based at least in part on the temperature profile. The method of claim 19, wherein the angular position is determined based at least in part on the position of one or more support pins in the millisecond annealing system.